Spark control device for internal combustion engines



April 24, 1934. UD 1,956,332

SFARK CONTROL DEVICE FOR INTERNAL COMBUSTION ENGINES Filed Oct. 24. 1929 I mm Arvin 7' 4? Patented Apr. 24, 1934 P AT NT FFICE SPARK CONTROL DEVICE FOR INTERNAL COMBUSTION ENGINES Ludwig Nudl, Northcete, Australia, assignor to Nudls Patents Proprietary Limited, Melbourne,

Victoria, Australia Application October 24, 1929, Serial No. 402,233 In Australia October 31, 1928 4 Claims.

This invention relates to a device for observing and controlling the sparking action of ignition plugs in internal combustion engines whereby any misfiring or fault in the sparking in one or more of the engine cylinders may be immediately located and corrected so as to ensure a positive and efiicient spark notwithstanding that the spark plug points or electrodes may become damaged or coated with soot, oil or other foreign matter.

The invention has particular advantages in its application to aviation engines owing to the elimination or minimizing of risks incurred due to faulty sparking or misfiring, but it will be obvious that the invention is also applicable to automobile engines and internal combustion engines in general.

Besides ensuring a positive and efficient spark notwithstanding fouling of or damage to the spark plug points the invention enables the spark to be adjusted to suit varying conditions in the different engine cylinders thus ensuring proper explosion and preventing carbonizing of the cylinders and pistons and condensation of the gas mixture which is liable to cause leakage of the condensed fuel past the pistons and dilution of the oil in the crank case. The invention also ensures cooler running and reduced fuel consumption. 1

Briefly the invention consists in interposing in an ignition circuit between a magneto or distributor and a spark plug, a device for producing a spark gap which is visible and may be adjusted to thereby vary the length of the gap and thus increase or decrease the intensity of the spark created across the points of the spark plug. The adjustable spark gap device or the spark points thereof may be enclosed within a glass tube or the like so that the sparking of each of the engine cylinders may be continuously under the observation of the pilot, driver or attendant and any fault in one or more of the spark plugs may be immediately located and corrected by adjusting the visible spark gap as aforesaid.

But in order that this invention may be better understood reference will now be made to the accompanying sheet of drawing which is to be taken as part of this specification and read herewith:

Figure 1 illustrates a device in accordance with the invention.

Figure 2 is a cross section of the device seen in Figure 1.

Figure 3 is an enlarged detail of a negative sleeve or capacitor embodied in the device.

Figure 4 is an enlarged detail of a positive sleeve also embodied in the device.

Figure 5 is a front View, partly in section, of an embodiment of the invention suitable for a six cylinder engine.

Figure 6 is a cross section of Figure 5.

Figures 7 and 8 illustrate a device according to the invention applied to an instrument board.

Figure '9 is a diagram showing a plurality of devices connected between a magneto and series 65 of spark plugs.

Figure 10 is a diagram showing a plurality of devices connected between two rnagnetos and series of plugs.

A device in accordance with this invention comprises a first or adjustable electrode 2 which may consist of a screw and is adapted to extend through a metallic sleeve 3 having a screw threaded aperture 4 for the electrode 2. A terminal pin 6 may project from the sleeve 3 to receive a conductor 5 leading from a magneto, distributor or a source of electric current. The electrode 2 is adjustable in relation to a stationary or second electrode 7 which may also consist of a screw. Between the adjacent ends of the first and second so electrodes a visible and adjustable gap 8 is formed across which the current is caused to jump. A third electrode 9 which may also consist of a screw may be stationary, or, if desired, adjustable in relation to the second electrode 7, is also pro- 5 vided to form a second gap 11 between one end and the adjacent end of the second electrode across which gap the current is caused to jump. The third electrode passes through a metallic sleeve 12 to which is connected a terminal pin 13 0 adapted for connection to a wire or conductor 10 leading to a spark plug.

The aforementioned parts are suitably arranged and supported so that the gap 3 between the first and second electrodes is visible to the pilot, driver 'or other person in charge of the engine so that when the device is in use any fault in the functioning of the spark plug may be immediately perceived by the'corresponding weakening or discontinuance of the spark across the gap 8 and may be at once remedied by manipulation of the adjustable electrode 2 to thereby increase the strength of the current and the spark produced by the spark plug. If the third electrode 9 is stationary, as indicated in Figures 1 and 2, there 5 will be no need for the gap 11 between the second and third electrodes to be visible, but if the third electrode is adjustable then this gap 11 may also be visible. I

The support for the elements of the device may no comprise blocks 14 of insulatory material in which the sleeves 3 and 12 are retained, the blocks being held in spaced relationship by bolts 16 encircled by insulatory tubes 17. The second electrode may be clamped by nuts 18 to an intermediate insulatory plate 19.

Whilst any suitable metals or alloys may be employed in the construction of the various electrodes, sleeves and terminal pins, I have found that particularly satisfactory results are obtained where the following metals are employed. The terminal pins 6 and 13 should preferably be of mild steel. The sleeve 3 preferably comprises an outer annulus 21 of Lowmoor iron or Swedish iron, but Lowmoor iron is preferred, and an inner annulus 22 consisting of an alloy of zinc, tin, phosphor tin and aluminium in the proportion of, zinc about tin about 15%, phosphor tin about 5% and aluminium about 5%. This sleeve 3, owing to its molecular formation is purely negative in action and. has the tendency to attract high tension current which in turn alters the molecular formation. The sleeve 3 may be said to constitute a capacitor. When the sleeve becomes fully charged the current reaches a high state of excitation before the current can pass along the first or adjusting electrode which passes through the screwed aperture 4 in the inner annulus of the sleeve 3.

The first or adjustable electrode is preferably composed of an alloy of copper and tin in the proportion of, copper about 90%, and tin about 10%. As high frequency current tends to fiow to a point, the lower or current egress end por tion 23 of the adjustable electrode 2 may be pointed or of conical formation, and the adjacent or ingress end portion of the second stationary electrode preferably has a flat top or enlarged head 24. This construction overcomes any tendency of the current to flow back from the second to the first electrode. The second electrode 7 is preferably composed of Delta metal and its lower or egress end portion 26 is also preferably pointed or of conical form, for the reason above stated. This electrode 7 functions as a conductor and is composed of Delta metal in order to prevent oxidation. The nuts 18 encircling the second elec trode are also preferably composed of Delta metal. By Delta metal, appearing herein and in the claims, there is intended to be described an alloy on the market under the name of Delta metal made up of copper, zinc, lead, iron, manganese, nickel and phosphorous, the lead, iron, manganese, nickel and phosphorous being in relatively small proportions.

The third electrode 9 is preferably composed of copper, phosphor tin and aluminium in the proportion of, copper about 75%, tin about 15%, aluminium about 10%, and is provided at its upper end with a fiat portion or head 27, to prevent backfiow of the current to the second electrode.

The sleeve 12 associated with the third electrode preferably comprises an outer annulus 28 of Lowmoor iron or Swedish iron, and an inner annulus 29 of copper, tin and aluminium in the proportion of copper about 75%, tin about 15%, and aluminium about 10%. This sleeve 12 constitutes a positive base through which the current passes to the terminal pin 13 from which a cable or rod leads to the sparking plug.

By constructing the various elements as above described I have found that it is possible to obtain very high amplification of high tension or frequency current and. to produce a spark across the points of a sparking plug which is of extreme intensity or strength and of relatively long duration even if the points of the plug are fouled, damaged or spaced from each other too great a distance to enable an efficient spark to be obtained under normal conditions. In fact with a device in accordance with this invention it is possible to produce at the sparking plug an intensely incandescent ray which will endure throughout the firing or power stroke of the engine piston. Such a ray will ensure that the oil or gas mixture whether rich or poor will be completely ignited or exploded.

According to a practical embodiment of the invention a plurality of the visible and adjustable spark control devices may be assembled within a suitable casing 30, composed of insulating material, as seen in Figures 5 and 6, provided in its front wall with suitable inspection facilities such as sets of windows 31 aligned with. the gaps between the first and second electrodes and between the second and third electrodes, the latter in this case being adjustable in relation to the second electrodes as will be seen in the drawing.

If desired the second electrodes and the adjacent parts of the first and third electrodes may be enclosed by glass tubes 32 as indicated in Figures 5 and 6.

In the arrangement illustrated in Figures 7 and 8 a casing 30 containing a series of the spark control devices is attached to the rear of an instrument board 33 provided in its front with window openings 34 which may be backed by glass or mica whereby the gaps between the first and second electrodes are visible. Access may be had to the heads of the first or adjustable electrodes by way of an opening 36 in the instrument board above the windows, this opening being normally closed by a hinged or other suitable fiap 37.

As indicated in Figures 9 and 10 two or more spark plugs 38 may be electrically connected to the sleeve 12 of each control device, while the sleeves 3 may be connected to a magneto 39. If desired however two: or more magnetos 39 or distributors may be connected to the sleeve 3 of each of a number of the devices so that in the event of failure of one magneto or distributor, efficient sparking may still be obtained through the medium of the magneto or distributor remaining in operation.

Numerous important advantages are attainable by the use of the present invention. The intense and prolonged spark or incandescent ray produced by the sparking plug ensures complete combustion of the fuel and results in increased power and quicker acceleration. The complete combustion obtainable prevents carbonization, overheating and pro-ignition and tends to prolong the effective life of the engine. Furthermore with the present invention it is possible to use lower grades of fuel and yet obtain equal if not better working results. The points of the spark plugs are unlikely to become fouled or carbonized and even if so it will not be necessary to clean same. In fact it is possible with this invention to obtain satisfactory ignition with worn, dirty or damaged plugs which would be inoperative in ignition systems not incorporating the present device.

The visible indication afiorded, by this invention, of the strength of the sparks or rays produced in the engine cylinders enables the pilot, driver or attendant to readily ascertain and correct any ignition faults and to regulate the fuel feed and other controls so that the maximum efficiency may be obtained.

The invention is particularly advantageous for use with multi-cylinder engines as it enables sparks or incandescent rays of different intensity to be produced in each cylinder of the engine if so desired. Thus in instances where there are variations in the compression obtaining within different cylinders the strength of the spark or ray in any particular cylinder or cylinders may be increased or decreased without affecting those of the other cylinders. The important advantage of being able to independently control the sparking in the different cylinders will be readily appreciated, and is unobtainable with existing ignition systems.

If desired the sleeves 3 and 12 may comprise inner and outer annuli of Lowmoor iron spaced apart and connected by radial arms or Webs to provide pockets which are filled with an alloy of copper, tin and aliuminium reduced to powder form.

Having now described my invention what I claim as new and desire to secure by Letters Patent is:-

1. A spark control device for the ignition system of internal combustion engines adapted for connection in the ignition circuit between the magneto or the like and the spark plug, said control device including blocks having an outer annulus of high grade iron and an inner annulus of an alloy of zinc, tin, phosphor tin and aluminum, and electrodes adjustably mounted in the blocks and composed of an alloy of copper and tin.

2. A device according to claim 1, wherein one of the electrodes is composed of an alloy of copper, phosphor tin and aluminum.

3. A device according to claim 1', wherein the electrodes are aligned, one of the electrodes being composed of an alloy of copper and tin and the other aligned electrode being composed of an alloy of copper, phosphor tin and aluminum.

4. A device according to claim 1, wherein the electrodes are three in number and arranged in adjustable alignment, the first and third electrodes of the series being composed of alloys including copper and tin and the intermediate electrode of the series being composed of Delta metal.

LUDWIG NUDL. 

